PROJECT SUMMARY Objective: The broad, long-term objective of this project is to advance understanding of ways to prevent unintentional prescription opioid poisoning. Specifically, the objective (FOA CE-10-002 objective #6) is to examine the ability of a publicly-sponsored physician education initiative to contribute to change in physician prescribing patterns, and to reduction in prescription opioid-related morbidity and mortality. Importance: Washington State (WA) is in the upper tier (10.8/100,000 in 2005) of unintentional poisoning mortality in the U.S.. In response to this public health epidemic, the Washington State Interagency Guideline on Opioid Dosing for Chronic, Non-Cancer Pain was developed by a consortium of Washington State agencies and clinical experts in pain management, and implemented in April, 2007. The Guideline focused primarily on dosing guidance for chronic non-cancer pain at or above a "yellow flag" dose of 120 mg/day morphine equivalent (MED). A gap in knowledge is the extent to which the Guideline has affected physician opioid prescribing practices, and whether it has reduced opioid-related poisonings. By evaluating the association of the Guideline with opioid prescribing practice, including specific dosing patterns, and with opioid-related morbidity and mortality, the proposed project will further understanding of effective means of preventing unintentional prescription opioid poisonings . Objectives: Specific Aim 1: Determine the extent of Guideline diffusion, adaptation of best opioid prescribing practices, and acceptance of the dosing "yellow flag". Hypothesis 1: At 3.5 years post-Guideline implementation, compared to 1.5 years post-implementation, both diffusion of the Guideline and adaptation of best opioid prescribing practices will have increased. Specific Aim 2: Examine changes in opioid dosing patterns within the WA Medicaid and workers'compensation populations after dissemination of the Guideline Hypothesis 2a: Over the three years after dissemination of the Guideline, as compared with before, chronic non-cancer pain patients receiving opioid prescriptions will be less likely to receive daily opioid doses exceeding 120 mg/day MED. Hypothesis 2b: The percent of patients receiving prescriptions >120 mg MED will decrease from year 1 to year 3 post-Guideline implementation. Hypothesis 2c: After dissemination of the Guideline, as compared with before, patients already on daily opioid doses above 120 mg/day MED will show lower average doses over the next three years, with a progressive reduction in average daily MED between year 1 and year 3. Specific Aim 3: Compare rates of non-fatal opioid overdose morbidity (as indicated by opioid-related hospital admissions and emergency department visits) and mortality within the WA Medicaid and workers'compensation populations, and of opioid-related hospitalizations and mortality within the statewide general population, in the three years after Guideline dissemination versus the three years before. Study Design: For Aim 1: Web-based physician survey For Aims 2 and 3: Retrospective cohort design involving analyses of independent cohorts of incident and prevalent cases of opioid users, and time series analyses to examine opiate-related morbidity and mortality Setting: WA State Participants: All WA Medicaid enrollees and workers'compensation claimants, identified from administrative databases, who are receiving prescription opioids for chronic, non-cancer pain. Over 30,000 Medicaid patients and over 10,000 workers'compensation patients begin receiving opiate prescriptions for chronic pain each year. Approximately 5% to 10% of Medicaid and workers'compensation patients prescribed opioids receive doses >120 mg/day MED. Interventions: Statewide implementation and diffusion of the Washington State Interagency Guideline on Opioid Dosing for Chronic, Non-Cancer Pain Outcome Measures: Percent of physicians using the Guideline and using opioid prescribing best practices;percent of WA Medicaid and workers'compensation cohorts prescribed 120 mg/day MED;trends in emergency department and hospital admissions for non-fatal opioid overdose;mortality trends 1 PUBLIC HEALTH RELEVANCE: Unintentional poisoning deaths related to prescription opioids have risen dramatically in the past decade, particularly among 35-54 year old adults. To address this public health crisis, the first Guideline in the US to address safe opioid dosing practice was implemented by all Washington State public payers in 2007. The goal of this proposal is to evaluate the impact of the Guideline. The project will test the hypotheses that in the three years post-Guideline implementation, compared to the three years pre- implementation, there is increased use of opioid prescribing best practices, a reduction in the incidence and prevalence of prescriptions of high dose (>120 mg/day morphine equivalent dose) opioids, and a decrease in opioid-asscoiated morbidity and mortality.